Electronic diplex transmitting distributor



June 29, 1954 A. E. CANFORA ET AL 2,682,574

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ATTORNEY A. E. CANFORA ET AL ELECTRONIC DIPLEX .TRANSMITTING DISTRIBUTOR June 29, 1954 8 Sheets-Sheet 2 Filed March 29, 1952 MNDFBSP JWJ M. A 5 E 0/ ...m www n H THU N P NM dit? June 29, 19.54

Filed March 29, 1952 A. E. CANFORA ETAL ELECTRONIC DIPLEX TRANSMITTING DISTRIBUTOR 8 sneets-shet s INVNTOR Herm/e E. ,aA/MEAN v Wmo/W HG1/oef ATTORNEY June 29, 1954 A. E. CANFORA ET AL ELECTRONIC DIPLEX TRANSMITTING DISTRIBUTOR 8 Sheets-Sheet 4 Filed March 29, 1952 dal@ Lid

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f ATTORNEY June 29, 1954 A. E. CANFORA ET A1. 2,682,574

ELECTRONIC DIFLEX TRANSMITTING DISTRIBUTOR FiledMarch 29, 1952 8 Sheets-Sheet 5 ATTORNEY June 29, 1954 A. E. CANFORA ET AL ELECTRONIC DIPLEX TRANSMITTING DISTRIBUTOR F'iled March 29, 1952 405 man; 0;- ve I If 8 Sheets-Sheet 6 ATTORNEY June 29, 1954 A. E. CANFORA ET AL 2,682,574

ELECTRONIC DIPLEX TRANSMITTING DISTRIBUTOR Filed March 29, 1952 8 Sheets-Sheet '7 ATTORNEY Patented June 29, 1954 ELECTRONIC DIPLEX TRANsMIT'rmG DISTRIBUTOR ArthurEugene-Canfora, Brooklyn, and Anthony Liguori,-New -York,'N. Y., assignors to Radiov Corporation .of America, a corporation of Bela Application March 29, 1952,"Seiial No. 279,432

18 Claims.; (Cl. 17S61) Theinvention relates to multiplex telegraph systems and particularly to electronic transmittingdiplex distributor*arrangements for such systems. Y

Essentially, a diplex transmitter is adistributor for converting a plurality of separately and-simulf taneously presented multi-element fixed-length code signals into an aggregated-serial signal in which the individual code signal elements-appear sequentially in time.

signal appearing over n separate circuits with the elements presented simultaneously or sequentially element after element.V An n-element simultaneous signal is construed to beone in Whichm signal elements appear simultaneously on n separate circuits, and a sequential signalis construed to be one in which n elements appear onA n sepa-v rate circuits element after element. A serial signal is construed to mean anr n-element signal appearing element after element-over a singlecircuit. A circuit arrangement for transposing from serial representationto a separatev presentation is referred to bythoseskilled in the art as aser-sep arrangement. Similarly, `circuit arrangements limited to serial and simultaneous' vpresentations are familiarly termedser-sim arrangements, and circuit arrangements -specically limited to serial and sequential presentation are familiarly called ser-seq arrangements. Prior art arrangements for mechanically performing this function are known.

These prior artdiplextransmitting distributors are Wholly mechanical vin nature, including'elecf tric` motors, mechanical commutators, ydistribu tors, relays and associated components of like construction. The manyof the=manufactured components `of such mechanical systems-are-specially designed. Such systems inherently call-for experienced and involved .procedures for maintenance of the commutator brushes; relay conetacts, commutator segments andso forth.

A system of multiplexV telegraphy now receiving considerable attention involves va pluralityof telegraph channelsv transmitting in one-direction between two stationsandalike numberof channels transmitting in the opposite direction. Noremally transmission takes place simultaneouslyv in both directions and, to a great-extent, independ-V ently as Well. Circuitr-y is provided in` each chan As usedhereinafter, a sepa-vrate signal is construed to mean ann-element` sociated transmitting Vchannel and a signal requesting repetition ofy the character mutilated is transmitted to the other'station. At this other station the receiving circuitry causes the transmitting channel vin question to repeat the character yunderconsideration. Such systemseicaciously may use transmitting (andreceiving) diplex distributors of the type herein described. Preferably, the improved diplex distributor vof the invention' is used to controler coordinate the functioning of the component parts of the overall system. The diplex distributor may incorporate circuitry which is not essential tothe diplex function in and of itselfv but which is necessary to the proper operation of the overall system.

It is an object of the invention to provide a transmitting diplex distributor comprising only readily available, general purpose electronic components.

It is a further object of the invention to provide a transmitter diplex distributor that is simple in operation and which does not require involved proceduresifor operation and maintenance.

A more specific object of .the invention is to provide-'an electronicdiplexV transmitting distributor arrangement incorporating means to reverse the polarity of the output signal corresponding to either or both of the input signals in response to a simple switching-operation.

A further specic objectof the invention is to obtain a substantially constant amplitude output signal from an electronic diplex transmitting disy tributor circuit arrangement despite wide variation in amplitude 'of the input signals.

Theseand other objects of the invention are attained in `an all electronic circuit arrangement including lan electronic commutator Wired as to forma signal elementgating arrangement for a plurality of channel signal input codes of any given number of elements each. These signal elements are presented to the diplex transmitting distributor simultaneously over a plurality of leads and are to be presented in serial form to the multiplexVV transmitter in sequential order over a single lead. Theelectronic commutator is arranged to operate in response to a plurality of timing waves harmonica-Hy related to a standardl mentsy are then'serially applied over a single lead' to a signal' regenerating circuit.

A phase lock pulse output at a particular phase' of the electronic commutator is provided for insuring that a signal element of one channel is followed by the proper signal element for the other channel in the total aggregation. Means also are provided to lock the electronic commutator of one diplex transmitter in phase with the commutator of another diplex transmitter sup plying this phase lock information. Another reference pulse output is provided for application to a receiving diplex distributor located at the same terminal for use in measuring the circuit loop time of a looped two-way circuit.

A polarity control circuit is also incorporated to automatically invert the conditions of output signal corresponding to mark and space where it is desired to depart from the assigned marking and spacing polarities of one or both channels. A phasing circuit is arranged to put a preassigned code group on one channel regardless of the channel signal input code groups by throwing a switch. The phasingcircuit is also arranged to control the polarity control circuit re gardless of input information so that the phasing signal output consists of a predetermined code group of predetermined polarity.

An example of apparatus according to the invention will be described in detail with reference to the accompanying drawing forming a part or the specification and in which:

Fig. 1 is a functional block diagram of a diplex transmitting distributor according to the invention;

Fig. 2 (Figs. 2c, 2b, 2c and 2d being taken together) is a schematic diagram of a circuit arrangement functioning according to the invention as outlined by the block diagram of Fig. 1; and

Figs. 3-9 are curves representative of the waveforms produced at various points of the circuit arrangement shown schematically in Fig. 2.

Referring to Fig. l there is shown a functional block diagram of a diplex transmitting distributor according to the invention. An electronic commutator II is so wired as to form a commutated gating arrangement for the channel A and B signal inputs at terminal groups I2 and I4 respectively. The distributor according to the invention may be lused with codes of any number of elements but the circuits shown and described in detail were designed for a code of the seven unit protected variety in which each character is represented by three marking and four spacing signal elements. These seven elements are presented to the-diplex transmitting distributor separately and simultaneously over seven leads and are to be presented to the eleotronic multiplex transmitter with which this circuit is designed to operate in serial order over one lead. Further details of such an electronic multiplex transmitter are given in the cepending U. S. patent application Serial No. 211,272 iiled February 16, 1951 (RCA 33,781) of E. R. Shenk, A. Liguori and A. E. Canfora. The electronic commutator is arranged to operate in response to a plurality of timing waves harmonically related to an input frequency wave derived from the electronic multiplex transmitter and applied at terminals I3 to a frequency divided chain I 5. The timing waves are permutated between gating control and'gating tubes to effect sampling of each of the seven elements of channel A sequentially, the seven elements of channel B being presented to the circuit simultaneously, and then effect sampling of the channel B elements While the A elements are still 4 being presented to the circuit. The sampled elements are serially applied over a single lead to an A and B channel output circuit I'I which shapes the signal and provides the desired output level for a given load impedance at terminals I9.

The diplex transmitting distributor according to the invention also provides the auxiliary functions for proper operation of the system as a whole. For four channels of seven unit operation, two diplexers will be necessary, one for the A and B channels and one for the C and D channels. The four channels are presented to the electronic multiplex transmitter in pairs, that is, A and B over one lead and C and D over another lead. The electronic multiplex transmitter in turn combines the signals from the two leads into an aggregate signal over one lead, preferably in the aggregation:

This aggregation is termed a sequentially interleaved aggregation. It is construed as sequential because each diplex signal in itself consists of elements A1 through Av followed by elements B1 through B7 for one diplex transmitter and elements C1 through Cv followed by elements D1 through D7 for -the other diplex transmitter. It is stated to be interleaved because each channel of a diplex transmitter presents the signal elements thereof alternately with a channel from the other diplex transmitter. The diplex transmitters must provide the means for insuring that channel A1 signal element is followed by the channel C1 signal element in the total aggregation. This is accomplished by providing a phase lock output, at terminals 2l which consists of a pulse output at a particultr phase of the electronic commutator El. The diplex transmitter is also able to receive this pulse, at terminals 23, and lock the electronic commutator in phase with the commutator of the diplex transmitter supplying this phase lock information. Thus, if two dipleX units are used, the AB diplex transmitter will bethe superior and the CD diplex transmitter will be subordinate to it.

The diplex transmitter according to the invention also provides another pulse output identical to the one just discussed but which serves another function. This reference pulse output, at terminals 25, is applied to a receiving diplex distributor located at the same terminal and is used there to measure the circuit loop time between two transmitting and two receiving diplex distributors providing two-way circuits such as those previously described.

It is conventional in telegraph signalling systems to make the marking polarity of one channel the spacing polarity of another channel. A polarity control circuit 27 is connected to automatically invert the conditions of mark and space betweenrthe two channels. If it is desired to depart from the assigned marking and spacing pola-rities of one or both channels, information to do so is presented to the proper polarity control input terminals 3l or 32 of the.

polarity control circuit 2l and the polarity control circuit 21 is caused to ignore the pre-assigned convention and deliver the signal polarities called for by the polarity control information.

A companion receiving diplex distributor is so designed that by pushing a button at the receiver and throwing a switch on the diplex transmitting 1 By throwing a switch on the, dipiex transmitting distributor. a phasing Signal generator v3i Puts a preassigned code groupron Ychannel A regardless 'ofthe' channelwn Asignall input code groups. The phasing signal generator 33 putsma preassigned code group on channel- A regardless of the channel lA signal input code groups. The phasing signal generator 33A. also takes controlr of the polarity control:circuitnregardless of polarity control input information with the result that the channel A output consistsI of a predetermined code group of predetermined polarityas long as the'phasing switch is in the phase adjustingv position.

The frequencydivider chain I5 preferably has a switch incorporated in the circuit to alter the overall division so that eight unit code may be used if it is desired without makingiany other changes in the circuit arrangement.

Timing .wvo generator...

Referring to Figs. 2a to 2d, there is shown a schematic diagram of an embodiment of the diplex transmitter according to the "invention, The timing wave generator l5', shown in Fig. 2b, comprises a conventional frequency dividing chain of ampliers'and bistable reciproconductive circuits triggered by a/synchr'onizing square wave, obtained from a frequency standard directly or indirectly through one of the associated components as available.

-As employed herein the term reciproconductive circuitv is construed to include all two tube regenerative devices in which conduction alternates in one or the other tube in response to applied triggering potential. The termV multivibrator is sometimes applied to this circuit and the'term locking circuit is sometimes applied to a bistable reciproconductive circuit, which is one in which two triggers are required to switch from one stable state to the other and return.

A preamplifier tube VIA, shownin Fig."2b, and

associated components `produce'a differentiated square wave which is impressed' on both grids of a reciproconductive circuit comprising tubes V2A and V2B to provide a square wave of 85% cycles per second. This wave is applied to the succeeding dividers by way of an isolating tube VSB. Eight tubes V24-V21B`are connected in a known ring circuit to divide this frequency by a factor of fourteen when a division factor switch SW2 is in one position and by a factor of 'sixteen' when the switch is in the other position. The ring circuit shown is essentially a conventional Eccles- Jordan circuit with the tube V28A as the feedback path for division by'fourtee'n and the tube VZBB as a voltage regulator device, to`provide the proper cathode voltage for these frequency dividers. The grid of one tube of each of `the last four reciproconductive circuits returns to -150 through a common resistorRZl, for the purpose of locking the. commutator ll'in apreassigned phasev relationship with 'another -identical unit for four channel operation,5 as will be explained later. y

The" curves 3l--3ll in Fig. 3 show the various waveforms at pertinent points of the.divider chain for the eight unit operation andthe 'curves dill-A07 in Fig.4 show the Waveformsl'which differ for the seven unitoperation. A companion lof Figs. -3 and 4'illu'strat'e'sj the. diifere'ncein' shaft 'speed of' an analogous mechanical'arrangement .or. felectronic commutation speed between theseven. andeight.unit operation.. The Voltage yvaveproducedat tubesNZA and. VHB iS equal, t0. the speed pt rotationcfan, analogous mechanical de vicegand these .speeds are cycles of revolutions per vsecond lfor:the ,seven unit case and l cycles or revolutionspensecondfor 3the. eight umtcase.

Electronic commutator.

Leads connected to the anodes of. thev tubes VZdA-VZ'IB, shown' in. Fig.. 2b, are interconnected through individual isolating'. resistors RIM-R161, shown invligs.v Zaand 2c .to form sixteen coincidence points in such. permutations that the voltage at one of thesecoincidence points is above ground' potential` for. a given length of time only and is below a specified negative potential for the rest of the. commutation period. This positive potential appears at each of the sixteen coincidence points in turn and constitutes the gating potential. :Each of the. sixteen points is tied to the grid of a coincidence .gateicontrolling triode whose cathode is at ground potential. Thus thel voltageat the anodes of tubes VIZA-VISB will vary from +75, volts to approximately +10 volts and. back to.+75 volts. This will occur for eachof'the 'sixteen triodes in succeeding order. for eight unit operation and for each of the fourteen triodes`VI2A-VI5A, VIA-VIQA for seven unit operation.

The curves 5th- 5H of Fig. 5 show the harmonically related waveforms of the anodes of the tubes in the counting'chain and from these waveforms, one can determine thel connections necessary to obtain the desired commutation for the eight unit case. It can be seen from this figure that the anodesv corresponding to a particular signal element are all. positive at only one time duringv the commutation cycle. other times three of the four anodes may be positive but this condition still gives anegative voltage at the grids Vof ,the coincidence tubes VI ZAf-Vl 9B. Each ofV these tubes therefore conducts only 1% of the total commutation time. It will also be note'd that themaximum conducting time is'governed by the reciproconductive circuit 240. This timeis equal to 1/2' the reciproconductiv'e Vcircuit24il or 11.66 milliseconds at an operating speed corresponding to C. P. S. This conduction time. is the same whether seven or eight unit operation is used.

The same waveforms and coincidence connections for the seven unit operation are represented by the curves Gill-'SM5 in Fig. 6. For seven unit operation the coincidence connections `are unaltered, a switch is thrown to include the reset operation from thevtube V26 A to thetube V24A. The channel signal velement scanning sequence is unalteredl except for the fact thatV the points AB and Bare'never positive. The A8 coincidence connections are made through `theresistors RI 32', meanrat andnlss to the anodes of the tubes V24A,'V2 5A, V26A. and V21B, respectively. A study f Fig.` 6 shows thatthes'e anodes are never simultaneously positive. The B8 coincidence connections' are mace thrdughfresistors nlsajm e5 Riss and' am to the anb'oes ofuieltubes vuil,l

the period of' curves of Fig. 6 it can be seen that these anodes are never simultaneously positive either. Therefore, the grids of the sampling or gating control tubes VISB and VISB never go positive on seven unit operation and consequently the corresponding anodes undergo no voltage change. This means that for seven unit operation the conduction of the tube VISA is followed by the conduction of the tube VI2A instead of the tube VISB and the conduction of the tube VISA is followed by the conduction of the tube VISA instead of the tube VISB thus eliminating two "commutator segments, one for the A channel and one for the B channel, leaving a total of fourteen segments The mode of operation which provides a single train of signals from the A and B channel signals will be described for the seven unit protected code which consists of three marking elements and four spacing elements per character.

Seven signal elements from a single source, for example a tape operated transmitting distributor, are presented simultaneously, one to each of the seven input terminals I2-I to I2--1 of identical characteristics provided for channel A. Assume a code group is presented to channel A inputs composed of signal elements 3, 4 and 6 marking and elements I, 2, 5 and 1 spacing. This means that terminals I2-3, I2-4 and I2--6 are at zero potential and hence the grids of tubes VSA, VSB, and VSB are at ground potential. The terminals I2-I, I2-2, I2-5 and I2-1 will be at -20 volts with respect to ground, thus causing the grids of the tubes V4A, VAB, VBA and VIA to be -20 volts also. When the coincidence sampling or gating control tube VI2A conducts, the negative transition is diierentiated in the circuit comprising a capacitor C8 and the associated resistors to form a negative pulse at the cathode of the tube VflA. This pulse amplitude is less than the volt signal bias on the grid of the tube VQA and therefore the common anode load resistor R'II remains at ground potential. Under control of the divider tubes V2 4A to V21B, the sampling tube VIZA ceases to conduct and the sampling tube VIZB conducts in the requiredsequence at the signal character rate and a negative pulse appears at the cathode of the tube VAB. This tube is also cut oil by the applied spacing signal so that no pulse appears across the load resistor R1 I. The negative pulse at the cathode of the tube VSA due to conduction of the tube VI 3A appears across the anode load resistor R1I, because the grid of tube VSA is at ground potential due to applied marking signal. The tube VSA acts somewhat as a diode allowing a negative pulse at the cathode to appear at the anode. The negative pulses will appear across the load resistor R1I through the tubes VSB and VSB when the tubes VI3B and VIAB conduct, due to signal conditions. No pulses appear through the tubes VSA and V1A when the tubes VI4A and VISA conduct due to the channel A signal code group applied.

Signal clement regenerator These negative pulses occurring in time relationship across the load resistor R1I are inverted and amplilied in an inverter tube V3IA and fed to the grid of a regenerator control tube V33A which is biased below cutol by means of resistors R259 and R210. The anode of the control tube VSSA is connected to one side of a bistable reciproconductive circuit 340 comprising cross-connected triode tubes V34A and V34B. This circuit is essentially a pulse signal regenerator. In

the cathode of the tube V34B negative pulses are developed through a diierentiating capacitor C62 and the back resistance of a unilateral impedance element shown here as a germanium diode DI. These negative pulses are relatively narrow and are applied at signal element rate to coincidence with the appearance of signal derived pulses on the grid of the control tube V33A. Both of these pulses tend to control the signal regenerator circuit 340, but the pulses in the cathode of tube V34B will control only in the absence of signal derived pulses at the grid of the control tube V33A. The pulses from tube V33A when present as determined by the signal conditions will control the conducting state of the signal regenerating circuit 340 by virtue of being greater in width.

Signal polarity reversing It it conventional operating practice to reverse the polarity of signal elements on adjacent channels. In the arrangement disclosed this polarity reversal is automatically made as the signal scanning proceeds from elements Av to B1 as described below. Assume the channel B signa1 input terminals IlI-I to I 4-1 receive the same code group as was assumed above for channel A. Pulses will appear across the load resistor R11 and consequently on the grid of the control tube V33A, shown in Fig. 2d, at the times when the corresponding gating tubes VI 1A, VI 1B and VI8B conduct. The signal regenerator circuit 34|! will respond exactly as for the scanning of the channel A signals. Referring to Fig. '1, an example of input signa1 is represented by curve 100, curves 'IDI-121 show the phase relationship of pulses formed at the cathode electrodes of gating tubes VdA-VI IA and curves 129 and 13| represent the pulses presented at the grid of the tube V33A and at the cathode of the tube V34B in response to the signal shown in curve 100. Curves 133 and 135 show the resultant direct and indirect output signal trains corresponding to the input signal represented by the curve 10 I. By taking the output signal from either the anode of tube V34A or V34B, the signal regenerator circuit 340 will provide signals of either polarity to permit one signal polarity to be used for channel A and the opposite polarity for channel B. A marking element is denned thus far as zero voltage signal input and a spacing element as -20 volts input `for both channels A and B. The output marking element for channel A at the output terminals I9 is chosen to be -20 volts and the spacing element as zero volts across a 10,000 ohm input resistor (not shown) This is termed "norma polarity for channel A. For channel B the exact reverse is desired, that is the marking element at terminals I9 is chosen to be zero volts and the spacing element as -20 volts. This is termed normal polarity for channel B. Channel A zero input must appear as -20 volts in the output while zero input to any of the channel B input terminals must appear as zero output voltage and -20 volts input for channel A must appear as zero volts in the output while 20 volts for channel B input must appear as 2O volts in the output.

The anode of the tube V34B is at its higher potential for a marking signal element input. Tracing the inversions involved in passage through the tubes V32B, V3IB and VSSB, it Will be seen that the output for mark through this circuit path is the lower of the two possible output potentials from the tube V3SB, that is -20 volts. The anode of the tube V34A is at its lower potential for a marking signal element input.

' 9 Tracing the inversions involved-fin passage through the tubes V32A, V3-IB and V35B, it'will be seen that the output for mark through this circuit path is the higher of the two possible output potentials from tube-V35B, that is zero volts. It is necessary, therefore, to block the path through the electronic switch tube V32A while the electronic commutator II scans the channel A signal inputs and then to v,block the path through the switch tube V32B while the commutator II scans the channel B signal inputs. The signal polarity control circuit 300, comprising a bistable reciproconductive circuit y300 consisting of tubes V30A and V30B in conjunction with two polarity reversing tubes V29A and V29l3 automatically accomplishes this signal reversing process. The voltage at the anodeshof the polarity control circuit 300 and the signal regenerator circuit 340 is either 60 volts orapproxirnately -3 volts. Assuming the anode of the tube V30A to be at 60, volts, the Yvoltage at the grid of the tube V32A is either -60 -or +30 volts approximately, depending on the state ofthe signal regenerator circuit 340. The cathode of the switch tube V32A is biased to about .8 volts and therefore when the tube V3 0A isconducting the signal path through the switch tube V32A is blocked. In this case, with the tube -V30B blocked the voltage at the grid of the switch tube V`V32B is either -30 or -3 volts approximately, depending on the state of the signal regenerator circuit 340. It is seen that the signal can be passed through the switch tube V323 depending on signal conditions at the input terminals I2. `When the tube V30B is conducting, the polarity control circuit "300 then blocks theV path through the switch tube V32B and opens the path through the other switch tube V32A. The locking circuit 300 -must therefore have the tube V3 0B blocked during the channel A scanning period and the tube V30A blocked during the channel B scanning period. `Ihefvgrid of the polarity` reversingA tubeV29B is tied -to the channel AI coincidence point, that at the `junction of the resistors RIM, RI05, R106 and RIO`I. At the start of channel A scanning this point becomes positive. Thej-reversingtube V29B vtherefore becomes conducting and producesa negative going pulse which is impressed on the grid of the tube V30B to blocl; it. vThis allows the applied signal elements from the anode of the tube V34B of the signal regenerator circuit 340 to bev used. Coincidence points AI, A2, Y A5 and -Al are at ground potentialand coincidence points A3, A4 and A6 are at a voltage of -20 volts. At the end of the channel A-scan, -thegrid -of the reversing tube VZEA which is tied vto the coincidence point BI, at the junction of resistors RISE, RI3'I, RI38 and RI39 becomes positive and the tube V29A conducts. This -negative going 4voltage isimpressed upon the grid of the tube V30A blocking it. Under these conditions the opposite phase of the signal is obtained from the signal regenerator circuit 360. rThe corresponding elements of the B channel output are then the reverseof the A channel, as desired. The-operation of the signal polarity reversing circuitry Vis illustrated by curves G01-SH3 of Fig. 8.- Y Y, Y, I

In some applications it may be desired to depart from the preassig/ned marking and spacing output polarities for channel'A or B or forboth simultaneously. This is accomplished by` applying an external control voltage tothe polarity reversing tubes. The external controlcircuitry is the lsame for both channels andV hence only the channel A control will be described.

At the instant that the grid oflpolarity reversing tube V29B becomes positive to trigger the polarity control circuit 300 to put normal polarity signals on channel A, a negative pulse'appears at the cathode of the tube VZ'ZOB from-the anode of the gating control tube VI2A to attemptto trigger the polarity controlA circuit 330 to reverse the polarity of the signals on channel 1A. This pulse is normally overcome by the normal controlling wave from the reversing tube V293. To make it eiective, prior to thegeneration of the pulse at the anode of the reversingtubefVfZilB,-

a positive voltage of +20 volts is developed across a resistor R242 in the cathode of the tube V29B from the external controlling source connected tolterrninals 32. Since the grid of the reversing tube V29B will only become 0 volts, the cathode voltage of the tube V29-B of +20 volts will not render the tube conducting as it would have normally. This allows the pulse in the= cathode of the tube V30B to cause it to conduct during the channel A scan instead of lblocking it as it would have otherwise. If the +20 volts is `supplied to the terminal 32 permanently the'channel A output signals will be reversed and likewise the-channel B signals will be reversed on application of potential to the terminals 3 I.

Phasing signal generator y A special phasing signal was mentioned as being required on the A channel output for receivingv equipment phasing purposes. This signal in practice is the same as that assumed previously for purposes of circuit explanation, that is signal elements 3, d and S of channel A` marking and this signal should always be of normal polarity.

This is accomplished by throwingV a. switch SWE tothe phasing position. Inso doing, resistors REI, R34 and rBAU.- are removed from ground and tied to volts through; a resistor R22. vThis. clamps the grids of thetubes VSA, VBl and VGB to .therespective cathodes. Since the cathodes of these tubes return to -150` volts through the resistorRZZ, fthe cathodes willbe at about .35 volts even if the signal voltage on these grids is -20` volts. l Y

With the grids at zero or +20 volts, these tubes will act as diodes for the respective commutating pulses and consequently the A3, A4 and A6 commutating pulses will appear across the load resistor R'I and ultimately controlthe signal regenerator circuit 340 and output signal regardless of the channel Ar input signals. The plates of the tubes VdA-V'IB will also be at -35 volts and since the cathodes of the tubes V4A, VIIB, VGA and VlA are at ground potential, these tubes cannot conduct at any time regardless of channel A signal conditions. The net effect is the same as putting the desired signal code at the channel A input terminals I2 but without having to resort to any speciallycoded-tape insertion at the tape transmitter. The normalnature of vthis phasing signal is assured -by divoroing the polarity control circuit 300 from both the internal and external controls. --Throvving the switch SWI to the phasing position connects the grid of the tube V30A to ground through a resistor R232. This action destroys the locking effect of thecircuit 300 and maintains the anode of the tube VtlB at the potential-required for normal signal operation of channel A.n Since the anodes of tubes VSA-VI I Bl are-all tied'together to the load resistor-RTI, these tubes cannot-respond -to the channel Bsignal inputs -because the anodes are at -35 volts while the respective 11 cathodes are at ground. This condition gives a steady output at terminals `i 9 of Zero volts during the channel B scanning period. The above feature insures against any possibility of having the desired phasing signal appear inadvertently in the B channel output signal train.

Four channel operation involving two diplex transmitting distributors requires that the commutators of both distributors be locked in a definite phase relationship in order to maintain the four channel signal aggregation outlined earlier. Each diplex distributor produces two similar puise outputs at terminals 2l and 25. One of these outputs is used to indicate total loop time between a transmitting and receiving diplex by comparing the phase difference between these dipleX units in the receiving diplex distributor. The other output is fed to the channel CD transmitting diplex distributor to lock it in the required phase relationship. This output is a positive going or zero volt rectangular pulse equal in length to one segment time or at one speed of operation, 11.66 milliseconds. When the tube VI2B conducts, the anode potential drop across the anode resistor R15 is brought out to the grid of a phasing pulse output tube V33B which is normally conducting and giving an output of l volts in 10,000 ohms at the output terminals 2l and 25 when properly terminated. The negative pulse impressed upon the grid of the output tube V33B blocks the tube for 11.66 milliseconds, giving zero output voltage during this time. Each unit is provided with phase lock input terminals 23. When used as an AB channel diplex transmitter phase lock information pulses from an associated diplex receiver are applied to terminals 23. When a diplex transmitter is operating on CD channel the above described phase lock pulses from the AB channel diplex transmitters are applied to terminals 23. This information is used to reset each of the ve reciproconductive circuits in the frequency divider chain I5 to the proper conducting state at the time the unit supplying this phase lock pulse is in the process of scanning the A2 signal element.

This reset operation need occur only when the rst phase lockpulse arrives. Since the speeds of both commutators are identical, at the next scan of Az of the AB diplex unit, the CD diplex commutator will already be in the correct scanning position.

The actual reset operation is as follows. When the phase lock pulse arrives, the grid of the gating control tube VIEA should be positive. If it is not already positive, the four divider tubes V20B, lVZEA, V26A and V2'IB, shown in Fig. 2b, are blocked by the phase lock pulse. These tubes have the anodes tied to the grid of the tube VI 6A and the grids are returned to 150 volts through the respective grid resistors and a common resistor R2i, shown in Fig. 2b, instead of to -150 volts directly. The phase locking input ampliier tube VIB is normally blocked and the phase lock pulse will make it conduct. The negative going transition of the anode of the tube VIB is differentiated by a capacitor Cl and the resistor R2! so that the grids of the divider tubes V24B, V25A, V2EA and VZ'IB receive a negative pulse by way of the resistor R2! and block the corresponding tubes. The phasing of the commutatore is thus xed with respect to each other. The input reciproconductive circuit 200 must be in a certain state of conduction upon the arrival of the phase lock pulse. If it does not, it is reset to this state in the following manner. At the end of the phase lock pulse the reset tube VIB is blocked. The positive transition occurring at this time is diiferentiated by the circuit comprising a capacitor C6, and resistors Rl l, RIZ and R20 to give a positive pulse at the grid of the tube V3A. This positive pulse causes the tube V3A to conduct through the anode load resistor RB causing the tube V2B to conduct. This is the desired state of conduction for the circuit 200 upon arrival of the phase lock pulse. The preceding operation on the circuit 200 puts it 180 degrees out of phase with respect to the corresponding reciproconductive circuit in the superior diplex transmitter. This insures that the commutation of one diplex unit occurs midway between the commutation of the other unit, which mode of operation is essential to proper signal aggregation. The curves 90 |-905 of Fig. 9 shows the in line commutation times possible in both diplex units if no phase lock is used. This is an undesired condition. The curve 901 illustrates the desired condition obtainable with phase lock control.

The transmitting diplex units described may be used as a source of local timing pulses at specified phases of the commutator if desired. These are obtained by tying the grids of pulse output amplifier tubes to the appropriate coincidence junction points AI to AIG as desired. These output pulses may be used for timing the local equipment associated with the system.

The following component part values were used in construction of an electronic diplex transmitting distributor as shown in Fig. 2 and described in the foregoing specification for an operating speed of 85 C. P. S. corresponding to a baud channel speed. Obviously, other values may be employed for other channel speeds and so forth.

Capacitors Reference No.: Value Cl 0.05 mfd. C6 0.0005 C1 .-0.D015 C8 0.005 C32, C33, C34, C35, C48 0.0001 C49 0.0002 C50 0.05 C62 0.0002

Resistors RI 10 kilohms R2 1 megohm R3 100 kilohms R4 500 kilohms R6 150 kilohms RH 1.2 megohms RIZ 1 megohm R13 16 kilohms RHI 82 kilohms RIS 1 megohm Ri 2 megohms RIT 1.2 megohms RIB 430 kilohms RIB 10 kilohms R20 560 kilohms R21 27 kilohms R22-R24 100 kilohms R25 22 kilohms R31, R34, R40 22 kilohms R'll 1 megohm R12 100 kilohms R13, R15 560 kilohms RIM-RIB? 4.7 megohms Rl92 75 kilohms ResistorslContinued Reference No. 'Value Rl93 33kil`ohms 'R194 lifltilohms RASS-RISE 2 megohms R191 1f megohm R198 910 kilohms RHS- R220 1 megohm R22I-R'222 v 2.7'kilohms R223 A'330'kil01ims R224 1 megohm R232 560 kilohms R238-R239 7 1 meg'ohm R240-R24I 2-r`negohms R242 j kilohrns R243 330 kilohins R269 16 -kilohms R210 5.1 kilohms Tubes V|A-`-V35A 1/2 Type 5963 vDiodes DI-'DE v1N34A germanium The electronic diplex `transmitting distributor shown in the schematic' diagram of Fig. 2 as actually built, operated from two'electronically regulated power supplies. One/power supply, having the negative terminal at ground potential, delivered +150 volts to all points marked or +150, +75 volts to those points so indicated, and volt'sto those points lso indicated, with the total drain at approximately 26 milliamperes.

The other power supply, having the positive terminal at ground potential, delivered -150 volts at approximately 26 milliamperes at points marked or 150.

The invention claimed is:

1. A multi-channel transmittingl distributor system for translating multi-element, xedlength code characters from separate and simultaneous form to serial form 'including' a signal element regenerator comprising a reciproconductive circuit having at least one stable state of equilibrium and complementaryl output circuits, means to trigger said reciproconductive circuit to one statev o f equilibrium at signal' element rate, means to apply pulses corresponding to signal elements of one nature tosaid reciproconductive circuit to trigger said circuit to the other state of equilibrium; whereby the output circuits of said reciproconductive circuit provide separate'output-sig'nal trains'of opposite polarity directly and indirectly representative of the input signals, an` electronic switching' circuit coupled to said signal element' regenerator circuit, `out put terminals coupled to said' switching circuit, said electronic switching'circuit vbeing arranged to connect said voutput terminals *selectively 'to the complementary output circuits of saidA signal element regenerator circuit in response to applied switching potential, a bistable reciproconductive system4 coupledy to said electronic switching circuitf to develop andj apply 'said switching potential, control circuits having complementary inputs lconnected tosaid reciproconductive system, -meansl to f apply -pulses "to" said reciproconductive` system;y at'chann'elrate to trigger the same to alternate states of conduction, meansto apply pulsesf'to oneeoff' the inputs of said control circuit toKr reverse the triggeringfof said reciproconductive"system, imeans to Vapply potential to the other'of'said inputs-to nullify the application' of the polarity reversingpulses,

afgating circuitfarrange'd to serially apply pulses indicativeofy applied input signal elements of Said one nature toA said reciproconductive circuit, andmeans to apply pulses derived from at least a portion of said gating circuits to said control circuits to determinethe polarity of the output signal train applied to said output terminals.

2. A multi-channel vtransmitting distributor system for translating*multi-element iixed length code characters from'simult-aneous form to serial form including a Isignal element regenerator comprising a reciproconductive circuit having at least one stable state of equilibrium and complementary output circuits, lmeans to trigger said reciproconductive to one state rof equilibrium at signal element rate, Lmeans to apply pulses corresponding to signal elements of one nature to said reciproconductive circuit to trigger said circuit to the other statel of equilibrium, whereby the output circuits of 'said reciproconductive circuit provide separate output signal trains of opposite polarity directly and indirectly representative of the input signals, an electronic switching circuit coupled to said signal element regenerator circuit, 4output terminals coupled to said switching circuit, said electronic switching circuit being arranged to connect said output terminals seleci tively to the complementaryoutput circuits of said signal element regenerator circuit in response to applied switching potential, a bistable reciproconductive system coupled' to 'said electronic 'switching circuit to develop and apply said switching potential, means to apply `triggering pulses to said reciproconductive system at channel signal rate to trigger the same to alternate states of conduction, means to apply other potentials to said reciproconductive system to reverse the sense of any triggering thereof, a signal gating circuit arranged to serially apply pulses indicative of applied input signal elements of said one nature to said reciproconductive circuit, and means to derive'said triggering pulsesfrom'portions of said gating circuits for application to said reciproconductive system to reverse the polarity of they output signal train applied to said output terminals on alternate channels.

3.A multi-channel transmitting distributor system for translating multi-element, xedlength code characters from simultaneous form to serial forrnincluding a `signal element regenerator comprising a bistable reciproconductive circuit having two states of equilibrium and complementary output circuits,`means to trigger said reciproc'onductivecircuit' to one state of equilibrium at signal element rate, means to apply pulses corresponding to signal elements of one nature to'said reciproconductive circuit to trigger said *circuitil to the other state of equilibrium,

whereby the output circuits of said signal element regenerator 'provide separate output signal trains of opposite polarity directly and indirectly representative of the input signals, an electronic switching circuit coupled to said signal element regenerator, output terminals coupled to said switching circuit, said electronic switching circuit being arrangedto connect Isaid output terminals selectively tothe complementary output' derived from separate channel portions of said gating circuits to'said reciproconductive system to reverse the polarity of the output signal train applied to said output terminals on alternate channels.

Ll. In a multi-channel transmitting distributor system for translating multi-element fixed length code characters from simultaneous form to serial form, a signal element regenerator comprising a reciproconductive circuit having at least one stable state of equilibrium and complementary output circuits, means to trigger said reciproconductive circuit to one state of equilibrium at signal element rate, means to apply pulses corresponding to signal elements of one nature to said reciproconductive circuit to trigger said circuit to the other state of equilibrium, whereby the output circuits of said reciproconductive circuit provide separate output signal trains of opposite polarity directly and indirectly representative of the input signals, an electronic switching circuit coupled to said sign-al element regenerator, output terminals coupled to said switching circuit, said electronic switching circuit arranged to pro` vide two alternate conducting paths upon application of predetermined switching potential to connect said output terminals selectively to the complementary output circuits of said signal element regenerator.

5. ln a multi-channel transmitting distributor system for translating multi-element xed length code characters from simultaneous form to serial form, a signal element regenerator comprising a bistable reciproconductive circuit having complementary output circuits, means to trigger said bistable reciproconductive circuit to one state of equilibrium at signal element rate, means to apply pulses corresponding to signal elements of one nature to said reciproconductive circuit to trigger said circuit to the other state of equilibrium, whereby the output circuits of said reciproconductive circuit provide separate output signal trainsof opposite polarity directly and indirectly representative of the 'input signals, output terminals, an electronic switching circuit comprising a pair of electron discharge tubes having grid connections individual to the complementary output circuits of said signal element regenerator, common cathode connections and common anode connections to said output terminals, a further switching element arranged to apply predetermined direct potentials between the grids and cathodes of said electron discharge tubes to connect said output terminals selectively to the complementary output circuits of said signal element regenerator.

6. In a transmitting diplex distributor, a signal regenerator including a bistable reciproconductive circuit having two cross-connected tubes arranged to conduct alternately, means to apply, pulses to one of said tubes at signal element rate to cause said signal regenerator to tend to produce output signal elements of given nature, means to apply pulses wider than the irst said pulses and corresponding tosignal elements of nature opposite to said given nature to the other of said tubes to produce output signal elements of opposite nature, an electronic switch circuit comprising triode tubes individually coupled to said reciproconductive tubes, an output circuit connected in common to said triode tubes, and switching means connected to said triode tubes selectivelyA torender one tube conducting and the other blocked, thereby to reverse the polarity of the output signal train.

7. In a transmitting diplex distributor a signal regenerator including a bistable reciproconductive circuit comprising a pair of cross-connected eleotron discharge structures having cathode, grid and anode electrodes, means to apply pulses of energy in the cathode circuit of one oi said 'structures at signal element rate to trigger said reciproconductive circuit to a condition of equilibrium wherein said one electron discharge structure is conducting and the other structure is blocked, a signal control tube comprising a control grid, a cathode connected to the cathode electrode of said other structure and an anode connected to the anode electrode of said other structure, means to apply pulses wider than the irst said pulses and corresponding to input signal elements of one nature to the control grid of said control tube to trigger said bistable reciproconductive circuit to the other condition of equilibrium, whereby potentials at the individual anode electrodes of said electron discharge structures form separate output signal trains directly and indirectly representative of the input signal train, output terminals, an electronic switching circuit coupled to said signal element regenerator, said switching circuit including a pair of electron discharge tubes having common anode connections to said output terminals, common cathode connections and grid connections individual to the anode electrodes of said cross-connected electron discharge structures, said means comprising bistable reciproconductive system with cross-connected electron discharge systems having the anodes thereof individually connected to the grids of said switching tubes to bias said switching tubes selectively to couple the anode electrodes of said electron discharge structures to said output terminals, means to apply differentiated pulses at channel rate in the cathode circuits of said electron discharge systems to trigger said reciproconductive system to alternate conditions of conduction, said means comprising control ampliiier tubes having anodes individually coupled to the grids of said electron discharge systems and having grid and cathode input circuits to apply pulses wider than channel rate pulses to the grids of said electron discharge systems, thereby to override the pulses applied to the cathodes to trigger said bistable reciproconductive system to a desired condition of conduction, means to apply a triggering pulse to the grid input of one of said control amplier tubes to trigger said reciproconductive system to a predetermined state of conduction, and means to apply a direct potential to said cathode input circuits to cause said reciproconductive system to the opposite state of conduction on application of said one pulse to the grid input circuit.

8. In a two-channel transmitting diplex dstributor for translating multi-element ixed length code characters, a signal regenerator circircuit including a bistable reciproconductive circuit comprising a pair of cross-connected electron discharge structures having cathode, grid and anode electrodes, a capacitor and a diode element connected as a differentiating network in the cathode circuit of one of said structures, means to apply narrow pulses of energy to said differentiating network at signal element rate to trigger said reciproconductive circuit to the condition of equilibrium wherein said one electron discharge structure is conducting and the other structure is blocked, a signal control tube comprising a cathode connected to the cathode electrode of said other structure, an anode connected to the anode electrode of said other structure and a control grid, means to apply pulses wider than the said narrow pulses and corresponding to input signal elements of one nature to the control grid of said control tube to trigger said bistable reciproconductive circuit to the other condition of equilibrium, whereby potentials at the individual anode electrodes of said electron discharge structures form separate output signal trains directly and indirectly representative of the input signal train, an electronic switching circuit coupled to said signal regenerator circuit, output terminals coupled to said electronic Switching circuit, said electronic switching circuit including a pair of triode tubes having common anode connections to said output terminals, common cathode connections and grid connections individual to the anode electrodes of said cross-connected electron discharge structures, said means comprising a bistable reciproconductive system including cross-connected electron discharge system having the anodes thereof individually connected to the grids of said switching tubes to said switching tubes selectively to couple the anode electrodes of said electron discharge structures to said output terminals, capacitors and diode elements connected as difierentiatng networks in the cathode circuits of said electron discharge systems, means to apply pulses at channel rate across said differentiating network to apply narrow pulses to said reciproconductive system to trigger the same to alternate conditions of conduction, said means comprising triode control amplifiers having the anodes individually coupled tothe grids of said electron discharge systems and having grid and cathode input circuits to apply pulses wider than said channel rate pulses to the grids of said electron discharge systems to override said channel rate pulses to trigger said bistable reciproconductive system to a desired condition of conduction, means to apply a triggering pulse to the grid input of one of said control ampliers to trigger said reciproconductive system to a predetermined state of conduction, means to apply a direct potential to one of said cathode input circuits to cause said reciproconductive system to be triggered to the opposite state of conduction on application of said triggering pulse to the grid input circuit corresponding to the one cathode input circuit, a gating circuit comprising a plurality of triode tubes, a plurality of gating control tubes having the anodes thereof connected to the cathodes of the corresponding gating tubes, a. common resistor connected to all of the anodes of said gating tubes and coupled to the grid of said signal control tube, means to apply harmonically related timing waves in predetermined permutations to the grids of said gating control tubes to pulse said gating tubes to an operating point just below conduction one at a time in succession, means to apply input signal elements to said gating tubes to produce said pulses corresponding to input signal elements of one nature, and means to apply pulses from the rst gating control tubes of each channel to said reciproconductive systems to control the polarity of the output signal train applied to said output terminals.

9. In a transmitting diplex distributor, a signal regenerator including a bistable reciproconductive circuit having two cross-connected tubes arranged to conduct alternately, means to apply pulses to one of said tubes at signal element rate to cause said signal regenerator to tend to produce output signal elements of given nature, means to apply pulses wider than the first said pulses andcorresponding to signal elements of nature opposite to said given nature to the other of said tubes to produce output signal elements of opposite nature, an electronic switch circuit comprising triode tubes individually coupled to said reciproconductive tubes, an output circuit connected in common to said triode tubes, and switching means connected to said triode tubes selectively to render one tube conducting and the other blocked, thereby to reverse the polarity of the output signal train, said switching means comprising a bistable reciproconductive system having two cross-connected tubes, means to apply pulses to said reciproconductive system at channel switching rate to reverse the polarity of the output signal train, said means comprising a channel gating control circuit.

10. In a telegraph signal transmission system, means to generate a plurality of harmonically related timing waves, a plurality of signal gating tubes normally blocked by applied potentials well below cutoff potential of the tubes, means to apply said timing waves to said signal gating tubes to raise the applied potentials on but one oi the gating tubes substantially to cutoff potential at a given instant, means to apply voltages representative of signal elements o a given code character simultaneously and indvidually to said signal gating tubes, and a signal element regenerator circuit connectedin common to said gating tubes.

11. In a telegraph signal transmission system, means to generate a plurality of harmonically related timing waves, a plurality of signal gating tubes, means to apply operating potentials to said signal gating tubes to maintain the same normally well below cutofl condition, means to permute said timing waves to said signal gating tubes to raise the condition of conduction of but one of the same to substantially out ol in succession, a common output load element connected to said gating tubes and means .to apply voltages representative of the signal elements of a given code character to said gating tubes simultaneously, thereby to reproduce said signal elements at said common load element consecutively.

12. In a telegraph signal transmission system,

means to generate a plurality oi harmonically related timing Waves, a plurality of signal gating tubes each having cathode, grid and anode electrodes, means to apply operating potentials to said signal gating tubes to maintain the same normally well below cutoi condition, means to apply said timing waves to the cathode electrodes of said signal gating control tubes to raise the condition of conduction of but one of the same to substantially cut off in succession, a common output load element connected to the anode electrodes ofk said gating tubes, and means to apply voltages representative of the signal elements of a given code character to the grid electrodes of said gating tubes simultaneously, thereby to reproduce said signal elements at said common load element consecutively.

13. In a telegraph signal transmission system, means to generate a plurality of harmonically related timing waves, a plurality of signal gating tubes each having cathode, grid and anode electrodes, a plurality of gating control tubes each having a cathode, grid and an anode, said gating control tubes being individually connected in the cathode circuit of said signal gating tubes, means to apply operating potential to said tubes to render said gating tubes normally well below cutoff, means to apply said timing waves to the grids of said gating control tubes to render but one of the gating tubes substantially at cutoff potential at a given instant, a resistor connected in common to the anode electrodes of said gating tubes, and means individually and simultaneously to apply voltages representative of the signal elements of a given code character to the grid electrodes of said gating tubes, thereby to reproduce said signal elements sequentially across said common resistor.

14. In a multi-channel transmitting distributor system for translating multi-element, iixedlength code characters from simultaneous form to serial form, a signal element regenerator comprising a bistable reciproconductive circuit having two states of equilibrium and complementary output circuits, means to trigger said reciproconductive circuit to one state of equilibrium at signal element rate, means to apply pulses corresponding to signal elements of one nature to said reciproconductive circuit to trigger said circuit to the other state of equilibrium, whereby the output circuits of said signal element regenerator provide separate output signal trains of opposite polarity directly and indirectly representative of the input signals, an electronic switching circuit coupled to said signal element regenerator, output terminals coupled to said switching circuit, said electronic switching circuit being arranged to connect said output terminals selectively to the complementary output circuits of said signal element regenerator in response to applied switching potential, a bistable reciproconductive system coupled to said electronic switching circuit to develop and apply said switching potential, control tubes connected to said reciproconductive system and having complementary grid and cathode input circuits, means to apply relatively narrow pulses to said reciproconductive system at channel rate to trigger the same to alternate states of conduction, means to apply wider pulses to the grid input circuit of one of said control tubes to reverse the triggering of said reciproconductive system, and means to apply potential to the cathode input circuit of said one tube to nullify the application of the polarity reversing pulses to the grid input circuit.

15. In a transmitting diplex distributor, a signal element regenerator circuit producing potentials at output connections thereof directly and indirectly representative of the input signal train, output terminals, an electronic switching circuit coupled to said signal regenerator circuit and including a pair of triode tubes having cornmon anode connections to said output terminals, common cathode connections and grid connections individually made to the output connections of said signal element regenerator circuit and a bistable reciproconductive system having two cross-connected electron discharge systems with the anodes thereof individually connected to the grids of said switching tubes to bias said switching tubes selectively to couple the output connections of said regenerator circuit to said output terminals, differentiating networks in the cathode circuits of said electron discharge systems, means to apply pulses across said networks to trigger said reciproconductive system to alternate conditions of conduction, triode control amplifiers having the anodes individually coupled to the grids of said electron discharge systems and having a grid input circuit to apply pulses to the grids of said electron discharge systems to override the differentiated pulses applied to the cathodes, and means to ap- 20 ply a pulse to the grid input of one of said control amplilers to trigger said reciproconductive system to a desired state of conduction.

16. In a transmitting diplex distributor, the arrangement as deiined in claim 15 wherein said triode control amplifiers also have cathode input circuits and means to apply a direct potential to said cathode input circuit to trigger said reciproconductive system to the opposite state of conduction on application of said one pulse to said grid input circuit.

17. In a transmitting diplex distributor a signal regenerator circuit including a bistable reciproconductive circuit comprising a pair of cross-connected electron discharge structures having cathode, grid and anode electrodes, means to apply pulses of energy in the cathode circuit of one of said structures at signal element rate to trigger said reciproconductive circuit to a condition of equilibrium wherein said one electron discharge structure is conducting and the other structure is blocked, a signal control tube comprising a control grid, a cathode connected to the cathode electrode of said other structure and an anode connected to the anode electrode of said other structure, means to apply pulses wider than the rst said pulses and corresponding to input signal elements of one nature to the control grid of said control tube to trigger' said bistable reciproconductive circuit to the other condition of equilibrium, whereby potentials at the individual anode electrodes of said electron discharge structures form separate output signal trains directly and indirectly representative of the input signal train, output terminals, an electronic switching circuit coupled to said signal regenerator circuit, said switching circuit including a pair of electron discharge tubes having common anode connections to said output terminals, common cathode connections and grid connections individual to the anode electrodes of said cross-connected electron discharge structures, said signal regenerator circuit comprising a bistable reciproconductive system with cross-connected electron discharge systems having the anodes thereof individually connected to the grids of said switching tubes to bias said switching tubes selectively to couple the anode electrodes of said electron discharge structures to said output terminals, means tc apply pulses at channel rate in the cathode circuits of said electron discharge systems to trigger said reciproconductive system to alternate conditions of conduction, said means comprising control amplier tubes having anodes individually coupled to the grids of said electron discharge systems and having grid and cathode input circuits to apply pulses wider than said channel pulses to the grids of said electron discharge systems, thereby to override the pulses applied to the cathodes to trigger said bistable reciproconductive system to a desired condition oi conduction, means to apply a triggering pulse to the grid input of one of said control amplifier tubes to trigger said reciproconductive system to a predetermined state of conduction, and means to apply a direct potential to said cathode input circuits to cause said reciproconductive system to the opposite state of conduction on application of said one pulse to the grid input circuit, a gating circuit comprising a plurality of triode tubes, a plurality of gating control tubes having the anodes thereof connected to the cathodes of the corresponding gating tubes, a common anode impedance element connected to all of the anodes of said gating tubes and coupled to said signal control tube, means to apply harmonically related timing waves in predetermined permutations to the grids of said gating control tubes to pulse said gating tubes to an operating point just below conduction successively, means to apply input signal elements to said gating tubes and means to apply pulses from the first gating control tubes of each channel to said reciproconductive systems to control the polarity of said output signal train applied to said output terminals.

18. A multi-channel transmitting distributor system for translating multi-element fixed length code characters from simultaneous form to serial form including a signal element regenerator comprising a reciproconductive circuit having at least one stable state of equilibrium and complementary output circuits, means to trigger said reciproconductive circuit to one state of equilibrium at signal element rate, means to apply pulses Ycorresponding to signal elements of one nature to said reciproconductive circuit to trigger said circuit to the other state of equilibrium, whereby the output circuits of said reciproconductive circuit provide separate output signal trains of opposite polarity directly and indirectly representative of the input signals, an electroni-c switching circuit coupled to said signal element regenerator circuit, output terminals coupled to said switching circuit, said electronic switching triggering pulses to said reciproconductive system at channel signal rate to trigger the same to alternate states of conduction, a signal gating Y circuit arranged to serially apply pulses indicative of applied input signal elements of said one nature to said reciproconductive circuit, and means to derive said triggering pulses from portions of said gating circuits for application to said reciproconductive system to reverse the -polarity of the output signal train applied to said output terminals on alternate channels.

References Cited in the file Of this patent UNITED STATES PATENTS Number Name Date 2,520,953 Norris et al Sept. 5, 1950 2,607,035 Levine Aug. 12, 1952 2,609,451 Hansen Sept. 2, 1952 2,609,452 Hansen Sept. 2, 1952 

